Pacar MX Engine fuel mileage

Discussion in 'Trucks [ Eighteen Wheelers ]' started by RDE1950, Dec 5, 2010.

  1. JDP

    JDP Medium Load Member

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    Dubuque, IA
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    ProudTrucker

    Thanks for the informative posts. I've been trying to analyze the engine situation for months. We need to make a purchase order for 6-8 trucks for late summer delivery. In 2010 we were able to get a dozen Pete 386s with EPA 2007 Cat C13s. Driver's obviously love the Petes so I was considering speccing T700s with the MX engine because I've heard the horror stories with Cummins. Anyways, I hope things get better for you. I don't know what kind of fuel economy numbers you're used to, but numbers like that would kill my bottom line.

    In an earlier post you mentioned that you strayed away from the T700 in favor of the T660. Can you explain your rationale? I liked the T700 because it has many characteristics of the Cascadia in terms of aerodynamics but I assumed the quality of construction would be much higher.
     
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  3. Scania man

    Scania man Road Train Member

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    God love you, unfortunately it all sounds all too familiar , a new truck shouldn't be giving you any problems but worse again the dealers are treating you like daf/pacaar treats it's customers here!
     
  4. Scania man

    Scania man Road Train Member

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    Saskatchewan
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    Don't even consider pacaar mx engines, whatever problems cummins have right now they can't be as bad ! The first one that failed on me did so at 145,000 miles, it didn't blow up it was worn out completely, it needed a full overhaul , engine no 2 wore out at 340,000 miles and that is about the service life of those engines normally! And to add insult to injury daf/pacaar wouldn't honour the warranty
     
  5. ProudTrucker

    ProudTrucker Bobtail Member

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    Mar 25, 2008
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    JDP,
    My decision to buy the T660's rather than T700's was based on the following reasons. We have been a Kenworth fleet since 1994 and have purchased W900's, T600's and T2000's in that time frame. The W900 being the most realiable and easiest to maintain followed by the T600 and then the T2000. We didn't purchase W900's because our hope was to get better fuel economy and cut our empty weight. The T660 closely resembles the T600 but is slighty improved. We've had bad experiences with the T2000 related to overly complicated HVAC systems, bad fitting doors, poor driver visibility, expensive windshield replacements that have to be glued in and a clutch that wasn't designed to accomodate the shorter driver. When I went to the Mid America truck show in Louisville I noticed that many of the design features of the T700 resembled the T2000. The engineers tried to convince me that they have corrected to failures of the T2000 but I decided to wait for more field testing. A few of the drivers that moved from T2000's are disappointed with the less room but we don't run team and our drivers are in every weekend and sometimes a night during the week. They admitted that the large cab tended to cause them to carry more personal belongings than needed which in turn increased empty weights and stress on cab mounts. Some of the cabs looked like my garage inside. LOL I don't have any experience with the T700 and the engineers could have been telling the truth about the improvements. I felt I was already taking a big enough chance with the MX and I didn't want to shake the bugs out of a new chassis for them too.
     
    JDP Thanks this.
  6. joseph1135

    joseph1135 Papa Murphy

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    The Highway To Hell.
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    I have a 2012 KW T700 with the Paccar MX. They just did a software update on it. I was getting between 6.2 and 6.4. Now I'm around 6.8 I just pulled an orange juice load from Florida to Michigan and held steady around there too.
     
    JDP Thanks this.
  7. ProudTrucker

    ProudTrucker Bobtail Member

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    To follow up on the unit that was down. The dealer replaced the module that was causing the DPF injector not responding code. The service manager told me that they installed a new program along with a sensor shield to correct issues related to my complaints and I should see better economy. This is a complicated process because they truck has to communicate with a server at Paccar and then a file is sent to dealer for the install. These engines aren't plug and play like the other engines in my fleet. Another cost involved for the operators new to this design is to cost of DEF (Diesel Exhaust Fluid). My trucks average using 2.5 gallons of DEF per 100 gallons of diesel fuel. I'm buying this in bulk at a cost of around $1.28 per gallon. It is much higher when my drivers have to purchase the product at a truck stop.
    I have had many conversations up the chain with Paccar representatives about my issues. I have a reputation with them as being an operator that monitors every penny with the numbers to back my complaints. One claim is that these engines need the overhead ran at 40,000 miles to improve fuel economy and that I won't attain my fuel mileage targets until then. My target is between 6.5 and 7.0 and so far that seems out of reach. The positives so far is that none of these engines are using oil and I have yet to have a power complaint.
     
    The Challenger, turnanburn and JDP Thank this.
  8. ProudTrucker

    ProudTrucker Bobtail Member

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    Thank you for the good news. Did they do the campaign with the sensor shielding also?
     
  9. JDP

    JDP Medium Load Member

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    Dubuque, IA
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    I'm running (6) 2012 Cascadias w/ DD13s and Blue Tec SCR. For a freightshaker, they're actually a very nice truck, especially in a fleet application. We currently have newer drivers in them, so I'd like to figure out a solution for senior drivers with Petes or KWs. Gliders are looking more and more appealing.

    Our experience w/ the engine and DEF system hasn't been bad. Typical sensors here and there but Detroit's new "Virtual Technician" software is very helpful. As soon as a code is thrown, my maintenance director gets a call and email saying if the truck can be limped to a dealer for service or needs to be shut down.

    Our trucks have a 23 gal DEF tank and can run about 5000 miles or 2 weeks between fills. We don't buy any DEF on the road.
     
  10. ProudTrucker

    ProudTrucker Bobtail Member

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    I have another update regarding my MX powered T-660's. The update that was performed to reduce false codes has worked and the engines have become trouble free since then. Oil consumption is virtually zero and the drivers have adapted to the engines and are becoming happier with the performance power wise. I am having the valves adjusted at the recommended 40,000 mile interval and the fuel economy is increasing on the units after the adjustment. I have just studied the print out from the ecm of the unit I had the valves adjusted on yesterday. These numbers are prior to the valve adjustment and should improve.
    Miles: 39987
    Driving fuel used: 6183.9
    Driving fuel economy: 6.47
    Total fuel used including driving, idling and regeneration: 6447.7
    Overall fuel economy: 6.20

    I saw the printouts from another fleet and they are achieving 7.1 mpg driving economy. I talked to the owner and he said this happened around the 70,000 mile mark. He attributed it to break in and driver adjustments to the new engines. I haul heavier than he does and my engine load factor is around 44% while his fleet is around 35%.

    I am becoming happier with these engines.
     
    larry2903 Thanks this.
  11. Hardlyevr

    Hardlyevr Road Train Member

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    Mapleton Depot,PA
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    What does that valve adjustment cost? When that engine came out and I saw that more frequent interval it made me wonder about operating cost vs. the lower frequency on an ISX.
     
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